Tag Archives: macro

Last week I was preparing to visit one of my favorite hunting grounds for insects and other critters. The nearby Hill Country Water Gardens is an amazing emporium catering to those who build and maintain ponds. Additionally, they are a very complete nursery with a wide variety of plants. The best thing for me is that they have many tanks and ponds with live water lilies and lotuses. These water features attract many varieties of aquatic insects, including dragonflies and damselflies.

As I was gathering equipment I was selecting the optics appropriate for the day. I knew that I needed more reach than standard macro lenses like my Nikon AF 60mm F 2.8 Macro Nikkor or my Nikon AF 105 mm F2.8 Macro Nikkor. These two lenses are great, but the magnification just is not enough. My longer, Nikon AF 200mm F 4.0 has more reach, but as a fixed lens, there is no angle of view versatility and it will not accept a teleconverter.

So, the tried-and-true solution is a mid-range telephoto lens, with the addition of a teleconverter and for close-focusing ability the addition of a short extension tube. Frequently, a prime lens like a 300 mm lens with a 1.4x or 1.5x teleconverter and a 10 to 25 mm extension tube works well. The arrangement allows a full frame sensor to produce a field of view of about 4 inches and will focus to about 2 feet. That’s perfect, but that arrangement still has no angle of view flexibility.

The answer lies with a zoom telephoto lens, a teleconverter, and if required, an extension tube. With a teleconverter and extension tube robbing the optics of light, a fast lens is most desirable. The solution is a Nikon AF 70-200 mm F 2.8 VR Nikkor lens. To it we add a TC-17EII AF-S teleconverter. This produces a focal length range from 119 to 340 mm and at 200 mm, a field of view of 3.5 inches wide on a full frame sensor. The good thing about this arrangement is that it will focus down to 3.6 feet (measured from the sensor- about 2.5 feet from the front of the lens), plenty close for dragonflies and similar insects.

As these minimum focusing distances are perfectly ideal for butterflies, dragonflies, damselflies, and other insects and creatures, there is no need for an extension tube. A 12 mm extension tube will produce a 3.0-inch field of view but will further reduce the effective aperture by an additional stop. In some cases, you need all the light you can get for best auto-focusing and low light situations.

Another benefit of not using the extension tube is the lens combination can focus to infinity. This is a great benefit for that surprise bird or other subject at greater distances.

As in all outdoor photography, a flash used as a fill flash about 1.0 EV below the ambient exposure helps produce images with lower contrast, higher dynamic range and with more motion stopping capability. All the images in this article, except the lilies, were produced with a Nikon SB-910 Speedlight at minus 1.0 EV.

The night skies are bigger in Texas! Join us during the dark of the moon for an afternoon and overnight photography experience that will be unforgettable. The workshop will be held at Mason Mountain in a very remote Texas location without light pollution to take advantage of the best night skies. The workshop begins at 1:00 PM the first day and ends after breakfast the second. Emphasis will be placed upon planning, locating dark sky destinations, and how to prepare for a night sky photography shoot. Photography techniques to be demonstrated include selection and use of the appropriate equipment, photographic stills of the stars and the Milky Way, star trails, time lapse star motion techniques and light painting with all the above. Outdoor hands-on photography will include location set-up and star photos of the Milky Way, star trails and landscape features. Transportation, meals and lodging not included.

Only time scheduled in 2018.

Back by Popular Demand!Macro & Close-up Photography Intensive in the
Texas Hill Country-
October 12-14, 2018$695.00

Learn to photograph our small world around us in the heart of the magical Texas Hill Country for a three-day photography workshop geared to shooting close focusing images. This highly-praised workshop will be packed with hands-on instruction to help you grow your close-up photographic abilities with newfound skills, tools, techniques and proficiency. The workshop will feature one-on-one instruction and demonstrations with abundant native Texas flora and fauna. Techniques will feature creating the perfect exposure, use of flash and lighting modifiers, one-to-one life size magnification, focus stacking, macro panoramas, and also include collecting, management, and photography of small animals. Photography will be in the field and lab setting. This workshop is held at Mo Ranch, a 500 acre facility located on the North Fork of the Guadalupe River with aquatic, woodlands, and limestone hill habitats. Meals and lodging included.

Few seats now available!

Most Popular:
Bird Photography in the Texas Rio Grande Valley- October 25-28, 2018$1,495.00

Come to the avian rich Rio Grande Valley for a hands-on bird photography workshop in the heart of South Texas. The workshop features hands-on instruction and intensive shooting in some of the best birding habitat available and specifically timed for the best South Texas specialty birds and migrants. The workshop will be held at the 700-acre Laguna Seca Ranch north of Edinburg, Texas, a purpose-designed ranch for bird photography.The ranch is preserved with all-native plants and animals and features constant-level ponds, and permanent photography blinds oriented for the best use of light. Each blind provides outstanding photographic opportunities. A highlight of the workshop is the favorite raptor shoot, featuring Crested Caracara, Harris’ Hawk, White-tailed Hawk, Black Vultures and more! At our workshop we bring the birds to you creating an outstanding South Texas birding and photography adventure! Meals and lodging included.

Many times when producing images of small subjects we find that there is insufficient Depth of Field (or depth of Focus) to render the entire subject sharply from front to back. Insufficient Depth of Field (DoF) is cause by three factors:

First, we understand that, in addition to exposure, aperture controls DoF. As we increase the F number we add DoF. However we may not be able to make a good exposure with a big F number like F22.

Another factor is that as we increase the focal length of our lens, the DoF becomes smaller. We could select a shorter lens, but that changes perspective and ability to focus close in the case of a macro lens.

The final consideration is that when the lens is moved closer, the DoF also becomes smaller. Thus we are our best enemy and must deal with self-imposed photographic criteria.

Therefore we have learned to use focus stacking to solve this problem. This requires a series of often many images, each made at a different point of focus from front-to-back. The images are blended into on in the computer using specialized software. The image of the bee (below) is an example of a stacked composite of 50 blended images.

The several images are captured using different points of focus. Some lenses change magnification as the focus is changes, creating alignment problems. The better approach requires moving the camera a measured increment between shots. A geared focusing rail (below) or an automated programmed focusing rail are specialized tools for changing the focal point without compromising image size.

Another system uses a rail incorporated into a bellows system to change focus but not scale, as pictured below. There are several choices from several manufacturers to accomplish this movement process.

Now comes the new tool on the market- The Helicon FB Tube. This new idea comes from the producers of Helicon Focus, the industry leader in image stacking software. Essentially it is an extension tube with integrated electronic micro-controller designed to enable automated focus bracketing in single or continuous shooting modes. The measured tube length is 13mm and adds somewhat to the magnification of the lens dependent upon the focal length. Mounted on the camera in the same way as a usual macro extension tube, Helicon FB Tube automatically shifts the focus by one step with each shot thus producing a stack of images of unlimited length that can be rendered into a fully-focused image.

Helicon FB Tube needs no additional hardware apart from conventional cameras and lenses. Helicon FB Tube has no optics and does not affect image quality. Helicon FB Tube settings are configured through an additional application for Android or iOS. The set contains: Helicon FB Tube with IR Receiver and LED Indicator; Front and Rear Caps; IR Transmitter – connects audio port of a smartphone and Extension cable for smartphone and IR Transmitter.

The unit has been tested and found compatible with a wide number of camera models and lens. Helicon FB Tube is available with mounts for Nikon and Canon cameras and AF lenses with built-in motor.

I tested the image focusing ability of the FB Tube making 15 focus step images of the acorns below using a step factor of 70. The camera was a Nikon D800 with the FB Tube and 105mm F2.8 Micro Nikkor. Selected aperture was F5.6. Electronic flash in TTL Mode within a softbox provided consistent light.

To set up the FB Tube a couple of simple settings are made on the smartphone device, including lens focal length, crop factor, aperture and step size. this was relatively straight-forward on my iPhone using the available ap:

The phone then transmitted the data to the FB Tube via an IR emitter plugged into the phone audio jack and aimed at the tubes receiver. as shown below.

To get started, the first focal point was focused manually at 3.0 CM on the rule. The rest of the images in the series were focused automatically by the FB Tube. Three of those images are shown below -the first, middle, and last- of the 15 image sequence.

The fifteen images were selected in the computer and rendered in Helicon Focus
Method B (depth map) in a normal manner, rendering sharp focus from front to back. Final adjustments for tone, color and sharpening was completed in Photoshop CC.

There are several procedures to make images for stacking. Moving the camera is simple and inexpensive. A manual rail is a bit of an expense, Fully automated, servo motor driven rails and associated accessories are often more than $600. In comparison, the Helicon FB Tube costs $200.

In late September I had the opportunity to visit the US Fish & Wildlife Service San Marcos Aquatic Resources Center to photograph several of the endangered aquatic species from the nearby Central Texas waters.

Located near the Edwards Aquifer, a prolific artesian aquifer, the center is involved with scientific research, including equipment and technology development, captive propagation technique development, habitat restoration, native species life history studies, and invasive species life history and control studies. The Center currently serves as a refuge for several listed aquatic species associated with the Edwards Aquifer and other Texas spring systems.

The hatchery also works closely with the faculty at local universities to provide volunteer, work, and research opportunities to undergraduate and graduate students in biology.

Artificial streams are the main aquaria for the center and use fresh water from wells drilled deep into the Edwards Aquifer. The water is filtered and chilled to temperatures suited for each species and circulated throughout the unit.

To facilitate the photography of these aquatic species, I used a macro tank photography technique with a small 2.5 gal. aquarium, an artificial habitat and background. To better confine the aquatic individuals, a second piece of glass in a vertical orientation was used to narrow the available space for the subject specimen.

Equipment included a Nikon D800 DSLR, 105mm F2.8 Micro Nikkor lens and a SB910 Speedlight in a Lastolite EXYbox softbox on a boom. A black cloth also on a boom with a opening slit for the lens was employed in front of the tank to prevent reflections on the front of the aquarium. The setup is illustrated below.

Great care was given to the safety of every living specimen. Before introduction of any living subjects, the aquarium, any underwater props and gravel substrate was thoroughly washed and sterilized to prevent contamination of the endangered species. This procedure was also repeated between the introduction of each subsequent species. Water was that of the specimen’s home enclosure.

Over the course of a morning I had the pleasure to photograph the Texas Blind salamander (Eurycea rathbuni), San Marcos salamander (Eurycea nana), Fountain Darter (Etheostoma fonticola), all from the Edwards Aquifer near San Marcos, Texas, and the Devils River Minnow (Dionda diaboli) from spring-fed streams in Kinney and Val Verde counties west of Uvalde, Texas.

OVERALL IMPRESSIONS

Upon reading of this new lens from Venus Optics I was skeptical of its performance. It always seems that when manufacturers try to put lots of capabilities into a single package, something ends up being a compromise.

Upon handling the product for the first time, I was impressed by the clean lines and smooth operation. The focus was smooth from minimum to infinity and required only a quarter of a turn of the barrel. The focus scale read in meters from 0.12m to Infinity. The barrel was also marked in Magnification units from 0.1:1 to 1:1. Upon focusing to minimum, the lens length increased only 1/4 inch, short for a macro lens. There was no turning of the barrel so filter orientation was not affected.

The aperture ring was marked from F4.0 to F32 and had no click stop detents. The separation of the aperture indices was very small and much care was required to accurately line up the index. The aperture ring was smooth and had no slippage.

It was interesting to note the lens had a Depth of Field Scale marked on the barrel, a feature seldom found on today’s electronic aperture lenses. The difference from max DoF to min DoF is a very small change of about 2mm rotation of the focus ring.

The lens is stated to be “Tilt-Shift” when in fact, the lens shifts up and down in the horizontal camera orientation only. No tilt is available. The shift moves +/- 6mm and is stopped by a locking lever and solid detents. The shift was somewhat stiff upon use. This should not be an issue on a tripod and may become smother with use.

NO SHIFT

FULL UPWARD SHIFT +6MM

Front filter threads are standard 77mm and with a lens of this wide angle thin filters must be used to prevent vignetting. The lens is supplied with a tulip shape lens hood and front and rear caps. When the lens hood is in place significant vignetting occurs in the full upward shift position of the lens on the Nikon D800 full frame sensor. This is said not to occur with a crop (APSc) sensor camera.

APERTURE

The first standard test was to measure exposure consistency along the full aperture range. The test was made with a standard photographic gray card in ideal, even illumination. Aperture priority mode and spot metering was used. The camera and gray card standard were tripod mounted. As previously stated the aperture markings were small and indexing was critical. Upon examination of resultant images it was discovered there was an inconsistency in exposure from wide open maximum aperture to minimum aperture.

Reflection density results are as follows:

•F4.0 = 58.7 • F5.6 = 58.9 • F8.0 = 57.8 •F11 = 54.2

•F16 = 52.6 • F22 = 48.6 •F32 = 41.1

FOCUS

Focus was evaluated using a standard Adobe Lens Calibration chart. Aperture selected was F11. Under image magnification, there was slight falloff at the horizontal ends of the frame, yet little falloff at the top and bottom of the horizontal frame.

RESOLUTION

Lens resolution tests could not be conducted empirically at this time in the studio/lab. However, when distant images were examined at magnification there were significant failures in sharpness both at the small and large ends of the aperture scale. It was perceived that only F8 and F11 were truly sharp. F4 and F5.6 were soft and F22 and F32 were unacceptable.

MINIMUM FOCUS DISTANCE

As a close focusing wide angle lens, this model performed as expected. Knowing that F8.0 was sharpest, several test images were made with near foreground and distant subject detail. This is an example of that performance.

The real test was to examine images shot near the Minimum Focus Distance while looking for distant background detail. Most wide angle lenses can produce tremendous Depth of Field; super wide angle lenses even more so. This lens employs a two stage focus where the near and distant focus occurs in one movement of the optic and extreme close up focus occurs as a result of a simple lens extension, similar to the use of a very thin extension tube. Expectations in performance due to that construction configuration were great.

When it came to the actual test, two things were rapidly apparent: the lens hood was in the way and the subject was so close to the front glass that it was often in shadow of the lens.

The first image of the flower and its environment was made at a magnification of 0.8:1 as marked on the lens barrel. It works rather satisfactorily. However, remember, I felt that F8 was the only sharp aperture which resulted in not having the detail in the background that I would have liked.

The second image of the flower was shot at 1:1 as marked on the barrel. It is nice and the center point of focus is very sharp. (See the cropped inset below). Interestingly, some of the flower petals are actually touching the front glass element. The lens hood was removed to get the flower in position and managing appropriate light on the flower was extremely difficult. These conditions were disappointing.

COLOR REPRODUCTION

In this series of samples, the lens did not reproduce any significant chromatic aberration. In a couple of the building images a very slight amount of red fringing was noticeable in the highlights at 10:1 magnification. What small amount of fringing present was easily corrected in software.

DISTORTION

As one can imagine there can be distortion with this lens just like any other super wide angle optic. And there is. What’s interesting is that when used correctly and held square to the subject there is little vertical perspective distortion. (See the building image above) But move only a few degrees from square and that error is extremely noticeable. (Below)

Fortunately for this lens the shift movement helps correct the issue. It is disappointing not to find the shift movement in both axes. Even old PC lenses have the ability to turn the barrel 90 degrees so that shift is available in both axes. (See shifted images far above.)

When used with vertical structures close to the edges of the frame, barrel distortion becomes evident. However software fixes are available for this error.

SUMMARY

For the LAOWA 15mm F4.0 Wide Macro lens to perform perfectly under all conditions was an exaggeration at best. The lens did well at many of the tasks performed. As a super wide angle lens it did well when used properly except for the higher F stops. As a macro lens, the detail was good near the macro end of the scale. Again, poor resolution at the higher F stops resulted in a lack of great Depth of Field. This is a shortcoming of lenses in the macro range but since F16, F22 and F32 are not sharp with this lens, this characteristic is a disappointing shortfall. In the two scenarios the use of the lens hood was a problem; when the lens was shifted upward (or downward) and when used at the close focusing distances.

For the casual shooter this can prove to be a useful lens, especially for the price. Canon and Nikon lenses are generally four times the price. And, to get the most from this optic, its shortcomings must be known and used in a manner that will minimize these shortfalls. When used properly and within known limitations, this lens canperform rather well.

For more specialized photographers however, the overall capabilities do not meet expectations. Both Canon and Nikon market top-of-the line tilt-shift lenses in focal length from wide angle to short telephoto. These lenses perform flawless at the tasks for which they were designed. These manufacturers also offer macro lenses in several focal lengths that produce macro images at 1:1 of the very highest caliber. If you need the best in these areas, you must pay the price.